(1) Technical Field
The invention relates to an apparatus for making pulse dampeners for use in fuel systems.
(2) Description of the Prior Art
One of the major concerns in the design, engineering and manufacture of the automobile is maintaining a quiet ride. In meeting these concerns, the automotive industry has endeavored to reduce, dampen or eliminate as much as possible the noise sources in the vehicle. One source of noise in the vehicle is derived from pressure pulses in a pressurized fuel line. More specifically, positive displacement fuel pumps as well as the on and off action of fuel injectors can cause undesirable "pulses" which create unwanted noise in the system.
Pulse dampeners are known in the prior art. Typically, a diaphragm-type accumulator is disposed along the fuel line between the fuel pump and the injectors. The pressurized fuel flows through an axial passage in the pulse dampener which includes an aperture which exposes a flexible diaphragm to the pressurized fuel. When a pressure pulse exceeds a predetermined level, the diaphragm flexes, thereby dampening the pressure pulses and smoothing out this operating parameter. Unfortunately, these types of pulse dampeners are relatively complex as compared to the subject invention and are much more expensive.
Other attempts have been made to reduce noise and dampen pulses in fuel systems by employing flexible members, typically made of a rubber based material, disposed inline in the fuel system for absorbing and dampening the pulses. Unfortunately, the desirable characteristics of these types of pulse dampeners in the prior art typically degrade with time when the material is exposed to gasoline or methanol.
The pulse dampener disclosed herein is manufactured using an apparatus and method which utilizes blow-mold technology. Methods and apparatus for making products using blow-mold technologies are known in the prior art. However, heretofore, it has not been possible to manufacture a pulse dampener of the subject invention utilizing blow-mold technology with the method and apparatus of the subject invention. The subject invention overcomes all of these deficiencies in the prior art in a very efficient, durable, and effective apparatus for making the pulse dampener disclosed herein.